Revascularization of ischemic bronchial anastomoses by an intercostal pedicle flap.

Ischemia of the donor bronchus, perfused solely by retrograde collaterals from the pulmonary circulation, is an important factor in the impaired healing of the bronchial anastomosis of transplanted lungs. The healing of two experimental models of bronchial anastomotic ischemia, the bronchial segmental autograft and the postpneumonectomy bronchial autograft, was assessed in dogs. The application of a polytetrafluoroethylene wrap to the bronchial segmental autograft and the application of an intercostal pedicle flap to the postpneumonectomy bronchial autograft, with and without concomitant administration of corticosteroids, were also studied to elucidate factors that affect bronchial anastomotic healing. The bronchial segmental autograft healed normally without stricture, but isolation of this autograft from the mediastinum and lung by the polytetrafluoroethylene wrap resulted in necrosis of the autograft. All dogs that had a postpneumonectomy bronchial autograft died of bronchopleural fistulas due to autograft necrosis. Application of an intercostal pedicle flap to the autograft resulted in healing in all animals. Arteriography and Microfil injection demonstrated revascularization of the postpneumonectomy bronchial autograft by the pedicled intercostal artery. Several conclusions can be drawn: With the lung in situ the bronchial segmental autograft survives, probably as a free composite graft. In contrast, the postpneumonectomy bronchial autograft is an excellent model of bronchial anastomotic ischemia. The intercostal pedicle flap is a reliable method for providing neovascularity and mechanical reinforcement to an ischemic bronchial anastomosis. Its effect on bronchial anastomotic healing was not diminished by administration of corticosteroids. The intercostal pedicle flap may be useful in preventing bronchial anastomotic complications in clinical lung transplantation.

Maintenance protocol for potential organ donors in multiple organ procurement.

Donor organs that are suitable for transplantation remain scarce, especially in view of the number of types of organ transplants now possible and the ever-increasing number of waiting recipients. This scarcity of donor organs can, to some extent, be ameliorated by the adoption of potential organ donor maintenance protocols that protect the organs from irreversible damage. Of key importance to the success of any such protocol is the establishment of hemodynamic adequacy and stability. Appropriate and vigorous antibiotic prophylaxis is also a major consideration, especially with regard to the pulmonary and genitourinary systems. The use of ophthalmologic preparations for protection of the corneas, attention to skin cleanliness, and the practice of rigorous sterile technique in the care of all indwelling catheters are measures that are strongly encouraged in order to provide the best possible chance of successful donation of organs that otherwise may be compromised.

Single lung transplantation with cyclosporin immunosuppression. Evaluation of canine and human recipients.

Cyclosporin, a potent new immunosuppressive agent, was used (alone or in combination with other drugs) in 28 canine single lung allograft recipients. Mean recipient survival with good allograft function was 155 days with cyclosporin and far exceeded that obtained in previous single lung allograft recipients treated with standard immunosuppression (15 to 22 days). The results of these experiments were as follows: (1) 20% of the recipient animals exhibited no evidence of rejection whatsoever; (2) four of 28 animals survived more than 350 days with good allograft function; (3) 79% of the animals exhibited some evidence of rejection that was easily reversed in 74% of instances with corticosteroids; (4) 10 of 28 animals exhibited good lung allograft function 5 months or more after operation; (5) in cyclosporin-treated lung allograft recipients, rejection was diagnosed by the presence of infiltrate on chest roentgenogram, analysis of the cellular content of bronchoalveolar lavage samples, and decreased perfusion on 99mtechnetium lung scan; (6) complete healing without stenosis of the bronchial anastomosis occurred in 82% of the animals studied. One of two patients treated with cyclosporin after undergoing single lung allografting survived 7 weeks after transplantation and 4 weeks after contralateral pneumonectomy. Episodes of rejection were reversible, and the bronchial anastomosis healed normally. This overall experience indicates that cyclosporin, although not a perfect immunosuppressive agent, increases the likelihood of success with therapeutic single lung transplantation.